U.S. Pat. No. 3,617,233 discloses a pneumatic invert mechanism for a glassware forming machine in which the neck ring arms are mounted for axial movement along the outer surface of a rack-driven shaft. Air pistons are formed at the opposed ends of the shaft and are coupled to air passages in the shaft to feed air under pressure to the pistons, and thereby open and close the neck ring arms, at the opposed ends of rotation of the shaft.
The present disclosure embodies a number of aspects that can be implemented separately from or in combination with each other.
An invert mechanism for a glassware forming machine, in an exemplary embodiment of the present disclosure, includes a support frame having a base adapted removably to be mounted on a forming machine frame. A linear actuator is suspended from the support frame and a linear gear rack extends from the actuator within the support frame. A hollow shaft has a central portion carried for rotation on the support frame and oppositely extending end portions with axial external splines and open ends. A gear is coupled to the central portion of the shaft for co-rotation with the shaft and has external teeth coupled to the gear rack. A pair of ball nuts are disposed on the end portions of the hollow shaft, and a pair of hollow pneumatic pistons are respectively disposed on the ball nuts over the open ends of the shaft. Invert arm mounts are respectively disposed on the pistons, and a spring is disposed within each piston operatively extending between the piston and the shaft to bias the pistons to a position adjacent to the support frame. An air inlet is disposed on the support frame adjacent to the gear. The gear has an air passage that couples the air inlet to the hollow shaft, and through the shaft to the respective pistons, at at least one angular position of the gear and shaft. The invert mechanism is adapted to be mounted as an assembly to the forming machine frame by means of the support frame.